1. Anatomy of the muscular subpulmonary infundibulum with regard to the Ross procedure 
Anna F Merrick, Magdi H Yacoub, Siew Yen Ho, PhD, Robert H Anderson, MD 
The Annals of Thoracic Surgery 
Volume 69, Issue 2, Pages (February 2000)
DOI: /S (99)

2. Fig 1
The heart has been prepared to show the relationship of the arterial roots. The pulmonary trunk has been tilted away from the aorta to show the extent of the subpulmonary infundibulum, and the extreme groove (between arrows) between it and the aortic sinuses giving rise to the coronary arteries. The aorta is cut at the sinotubular junction. Note the “flask” or “onion” shape of the aortic root. The white and black arrow indicates the first septal perforating artery, and the dotted line shows the circular junction between the wall of the pulmonary trunk and the muscular infundibulum.
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

3. Fig 2
This long axis through the ventricular outflow tract shows the sleeve of infundibular musculature that lifts the pulmonary valve away from the aorta. Note that the long axes of the two outflow tracts are at almost right angles to each other. The noncoronary leaflet of the aortic valve is in fibrous continuity with the leaflet of the mitral valve. (L, R = left and right coronary aortic sinuses.)
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

4. Fig 3
The relationship of aortic and pulmonary roots viewed from the front of the heart. The point of contact of the aortic and pulmonary sinotubular junctions is indicated.
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

5. Fig 4
The free standing subpulmonary infundibulum has been dissected away from the base of the heart at the lowest point of attachment of the valvar hinges. The arrow indicates the first septal perforating artery. Note the deep crevice between the remaining “septal” component of the infundibular sleeve and the base of the aorta.
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

6. Fig 5
The aorta and pulmonary trunk have been cut transversely across their sinotubular junctions, which are almost perpendicular, to show the relationships of the sinuses and the origin of the coronary arteries. Note how the zones of apposition of the facing arterial valvar leaflets meet at the level of the sinotubular junctions (star).
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

7. Fig 6
The walls of the aorta have been cut away to reveal a fibrous band (arrow), which connects the top of the interleaflet triangle between the right and left coronary aortic sinuses with the top of the interleaflet triangle between the right and left facing pulmonary sinuses.
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

8. Fig 7
This an enlargement of the dissection shown in Figure 4. The pulmonary root was removed by making a cut perpendicular to the attachment of the valvar leaflets throughout the root. Note that this cut has left a residual cuff of infundibular musculature, yet still permitted entire removal of the valvar leaflets. This would not be possible if a true muscular septum interposed between the pulmonary root and the left ventricle. The arrow shows the first septal perforating artery.
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

9. Fig 8
A band of fibrous tissue as it is seen in the operating room, positioned between the tips of the blades of the scissors.
The Annals of Thoracic Surgery  , DOI: ( /S (99) )